The invention relates to an apparatus for cleaning pasta presses, particularly for the cleaning in place of the screws of screw-type machines, kneader mixers and the like in the pasta industry, by a treatment with water, lyes and acids.
In the modern pasta industry, moistened doughs are treated with pressing and kneading screws in screw-type machines, in order to build up, with the formation of the dough, a glutinous structure and simultaneously to build up a high pressure for the moulding. Thus EP-B-351423, for example, describes a process and an installation for producing dough for pasta, wherein the installation comprises a double-shaft kneader having two shafts turning in the same direction which are, to a high extent, self-cleaning. A single-shaft press screw is employed for building up the pressing pressure. The double-shaft kneader and the single-shaft machine can be directly connected to each other, in order to prevent both an unwanted pressure build-up in the kneader and contamination due to external influences. However, despite the extensive self-cleaning of the double-shaft kneader, a high expenditure of manual labor is necessary in order to achieve satisfactory cleaning of the single- and double-shaft machines when the product is changed or for preventive cleaning. Dismantling is necessary, with subsequent cleaning (water and cleansing agent) and re-assembly.
Swiss Patent Application No. 1024/93, which has not previously been published, offers a partial approach to the solution of this problem. According to the invention, screws can be automatically ejected from screw-type machines in one stroke, and in a further development the single-shaft screw press is connected to a swivelling double-shaft kneader. Due to the swivelling capability of the double-shaft kneader, cleaning of the latter and of the connection zones to the screw press is possible in principle. However, with the exception of the screw ejection, the manner in which this is to be effected is neither disclosed nor evident.